Crash Data
The numbers of deaths and reported injuries from road crashes within New Zealand have, generally, declined fairly steadily in recent years (see Table E2). Despite the decline, the numbers of deaths and injuries on New Zealand roads – and the associated social cost62of these – are very high. In 1998, the social cost of fatal and reported injury crashes was approximately $2.77 billion (costed at 1999 prices).
Excess or inappropriate speed is a major contributing factor in road crashes (see Table E2). For example, in 1998, it probably contributed to 32% of fatal crashes and 20% of injury crashes. However, it is often difficult to determine if speed was a factor in a crash – it is rare for a driver to admit he or she was speeding. This means that the identification of speed as a factor
in a crash often depends on physical and/or witness evidence, and this may be inconclusive or unavailable. In general, speed is identified as a contributing factor in a crash if:
• either the police officer attending the crash reports that the driver was travelling at excess or inappropriate speed, and the Land Transport Safety Authority, whose staff code crash reports, agree with the officer and code the report with the factor “travelling too fast for the conditions”;
• or the Land Transport Safety Authority staff who code crash reports determine from the evidence in the crash report, and based on their experience, that speed prob-ably contributed to the crash.
Overall, it is assumed that speed is under-reported in data on crash factors because of the difficulty identifying it.
That is, it is assumed that there are a substantial number of crashes in which excess or inappropriate speed was a contributing factor but which could not be identified as
speed-1995 1996 1997 1998
Deaths
Total road deaths 582515 539 502
Deaths from crashes where speed was a factor 221 177 162 162
Percentage of total road deaths where speed was a factor 38.0 34.4 30.1 32.2 Serious Injuries
Total reported serious injuries 3,153 2,939 2,613 2,400
Reported serious injuries where speed was a factor 670 645 608 539
Percentage of total reported serious injuries where speed was a factor 21.2 21.9 23.3 22.5 Minor Injuries
Total reported minor injuries 13,717 11,857 10,764 10,012
Reported minor injuries where speed was a factor 2,318 2,161 1,917 1,896
Percentage of total reported minor injuries where speed was a factor 16.9 18.217.8 18.9
Table E2 – Casualties from all road crashes and where excess or inappropriate speed was identified as a contributing factor, 1995-1998
Source: LTSA Crash Analysis System.
62 “Social cost” includes all loss of life and life quality, medical treatment, related enforcement, and property damage. The cost of loss of life and life quality is the amount people are willing to pay to avoid the risk of death or injury from motor vehicle crashes.
related crashes. Furthermore, it is expected that there are a substantial number of crashes that are not coded as involving excess or inappropriate speed, but for which the injuries sustained in the crash would have been considerably less had the vehicle(s) involved been travelling at a lower speed.
Despite the limitations of the speed data, Table E2 demonstrates that, over the years 1995 to 1998, the number of injuries from crashes in which excess or inappropriate speed was identified as a contributing factor has declined slightly. However, the number is still very high and represents a significant proportion of the road toll.
The majority of deaths from crashes involving excess or inappropriate speed occur on rural roads. For example, 68%
of the deaths from crashes involving speed in 1998 occurred on rural roads (see Table E3), whereas the minor injuries from crashes involving excess or inappropriate speed were approximately equally likely to occur on urban or rural roads.
A similar proportion of rural to urban casualties occurs for crashes in which speed was not identified as a contributing factor. The higher speeds on rural roads are part of the reason there are more people killed on these roads. As we discussed in Part A of this review, this is because the higher the speed of a vehicle involved in a crash, the greater the injury severity for the vehicle occupants.
Table E3 – Casualties from rural and urban crashes with and without excess or inappropriate speed identified as a contributing factor, 1998
Source: LTSA Crash Analysis System.
Notes: “Urban” refers to all speed limit areas of 70 kph and under, and to limited speed zones; “Rural” refers to all speed limit areas of over 70 kph. The data refer to the number of casualties, not the number of crashes.
The proportion of all road deaths that occur outside urban areas (that is, in rural areas) in New Zealand is part-icularly high internationally. For example, 73% of the road crash deaths in New Zealand in 1997 occurred outside urban areas (Figure E4). Only in Norway, Spain, Austria, and Germany did a higher proportion (up to 80%) of deaths from road crashes occur outside urban areas in 1997. By comparison, in Japan, Poland, and Iceland, only just over 50% of road fatalities occurred outside urban areas.
Figure E4 – International comparison of percentage of road deaths that occur outside urban areas
Source: LTSA (1999c, Table 7, p157).
It is important to note that in urban environments there are high numbers of vulnerable road users, such as pedestrians.
Therefore, despite the lower speed in urban environments, these vulnerable road users have a high likelihood of being killed if hit by a vehicle. From 1996 to 1998, there were 132 pedestrians killed in crashes with a motor vehicle in urban areas. Of these 132 pedestrians, 13 were killed in crashes in which excessive speed was identified as a contributing factor (Table E4).
73
Rural Urban % Rural Crashes without Speed as a Factor
Deaths 240 100 71
Reported serious injuries 958 903 52 Reported minor injuries 3,128 4,988 39 Crashes with Speed as a Factor
Deaths 110 5268
Reported serious injuries 326 213 60 Reported minor injuries 991 905 52
50 60 70 80
Percentage of Deaths Outside Urban Areas Japan
74
Table E4 – Type of road user killed in crashes where excess or inappropriate speed was identified as a contributing factor, 1996-1998
Source: LTSA Crash Analysis System.
Notes: *Excludes motorcycle riders/pillions. “Urban” refers to all speed limit areas of 70 kph and under, and to limited speed zones; “Rural” refers to all speed limit areas of over 70 kph.
In crashes in which excess or inappropriate speed was identified as contributing to the crash, the speeding driver and his or her passengers are the road users most likely to be killed (Table E4). Speeding motorcycle riders also represent a high number of those killed in crashes in which excessive speed was identified as contributing to a crash.
In fatal and injury crashes involving excessive speed, by far the most common type of crash is one in which the driver lost control of the vehicle (see Figures E5 and E6).
The data shown in Figures E5 and E6 include both single-vehicle and multi-single-vehicle crashes. Single-single-vehicle crashes are those in which the driver lost control of the vehicle either on a straight or when cornering and collided with an object (or pedestrian) in the roadside environment; multi-vehicle crashes are those in which the driver lost control and crashed into another vehicle. The majority of crashes are, however, single-vehicle crashes. For example, of the fatal rural crashes in which excessive speed was a contributing factor and the driver lost control of the vehicle, 72% were single-vehicle crashes. Similarly, 76% of the fatal urban lost-control crashes involving excessive speed were single-vehicle crashes.
Figure E5 – Types of fatal crashes with excess or inappropriate speed identified as a contributing factor (annual average 1996-1998)
Source: LTSA Crash Analysis System.
Notes: “Urban” refers to all speed limit areas of 70 kph and under, and to limited speed zones; “Rural” refers to all speed limit areas of over 70 kph.
Figure E6 – Types of injury crashes with excess or inappropriate speed identified as a contributing factor (annual average 1996-1998)
Source: LTSA Crash Analysis System.
Notes: “Urban” refers to all speed limit areas of 70 kph and under, and to limited speed zones; “Rural” refers to all speed limit areas of over 70 kph.
The 15- to 24-year-old age group has the greatest number of drivers identified as travelling at excess or inappropriate speeds in fatal crashes (see Figure E7). Of the 15- to 24-year-old drivers involved in fatal crashes between 1996 and 1998, 35% were identified as travelling at excess or inappropriate speeds, compared to 17% for 25- to
Road User Killed Rural Urban Total
Speeding driver* 165 52217
Passenger with speeding driver* 111 48 159
Speeding motorcycle rider 3225 57
Pillion with speeding motorcycle rider 4 5 9
Pedestrian 3 13 16
Other road users 3210 42
Total 347 153 500 Number of Crashes
0 2 0 40 60 80
Urban Rural Overtaking
Head on
Lost control
Obstruction/Rear end
Intersection
Pedestrian
Other
200 400 600
Number of Crashes Urban Rural Overtaking
Head on
Lost control
Obstruction/Rear end
Intersection
Pedestrian
Other
0
75 64-year-old drivers. Hence, speed is disproportionally
represented in crashes involving a young driver. Across all age groups, male drivers involved in fatal crashes are also more likely to have been travelling too fast for the conditions than are female drivers. For example, 77% of the drivers involved in fatal crashes from 1996 to 1998 were males, and 85% of the drivers in fatal crashes involving excessive speed were males.
Figure E7 – Drivers identified as travelling at excess or inappropriate speeds in fatal crashes by age group (annual average 1996-1998)
Source: LTSA Crash Analysis System.
From 1996 to 1998, 21% of car and van drivers and 39% of motorcyclists involved in fatal crashes were identified as travelling at excess or inappropriate speeds (see Figure E8).
Only eight percent of truck drivers involved in fatal crashes were identified as travelling at excess or inappropriate speeds.
Figure E8 – Drivers involved in fatal crashes by vehicle type and by whether excess or inappropriate speed was identified as a contributing factor (annual average 1996-1998)
Source: LTSA Crash Analysis System.
Of the car or van and truck drivers identified as travel-ling at excess or inappropriate speeds in fatal crashes from 1996 to 1998, just over half (58% and 60% respectively) were killed in the crash. However, of the motorcycle riders identified as travelling at excess or inappropriate speeds in fatal crashes, the vast majority (89%) were killed in the crash.
This illustrates the greater vulnerability of motorcyclists over other vehicle occupants.
Travel Speed Data
The Land Transport Safety Authority conducts surveys of driver speeds at a sample of sites around New Zealand each year during winter. The survey involves unobtrusive roadside measurements of vehicle speeds over a period of about two hours. The speeds measured are for cars travelling at “free” speeds, unimpeded by other vehicles or by the road environment (the sites at which vehicle speeds are measured are on straight sections of road, away from traffic lights and intersections).
Table E5 displays the national results of the speed surveys since 1995. At the national level, rural mean speeds remained relatively constant from 1995 to 1999, with the exception of a decrease in speed in 1997 (the increase in mean speed from 1997 to 1998 was statistically significant at the five-percent level). In contrast, national urban mean speeds appear to have fallen each year since 1995 (although the differences from one year to the next are not necessarily statistically significant).
Table E5 – Speed data from the annual national winter speed surveys, 1995-1999
Source: LTSA Crash Analysis System.
Notes: The speed at the 85th percentile is the speed at or below which 85% of the vehicles travelled; that is, 15% of vehicles travelled above this speed. “Urban” refers to 50-kph speed-limit zones. “Rural” refers to 100-kph speed-limit zones.
Overall, from 1995 to 1999, mean speeds in both rural and urban environments at the national level were above the speed limit. The mean speed in the urban areas was further Number of Drivers
Age Group
15-24
25-34
35-44
45-54
55-64
65-74
75+
0 50 100 150 200
Not Speeding Speeding
Number of Drivers in Fatal Crashes Other
Motorcycle
Truck
Car/Van
0 200 400 600
Not Speeding Speeding
Speed 1995 1996 1997 1998 1999
Rural, mean 102.4 102.3 101.6 102.2 102.1 Rural, 85th percentile 115 115 113 113 113 Urban, mean 57.4 56.5 56.3 55.9 55.8 Urban, 85th percentile 65.5 63.5 63.0 63.0 62.5
76
above the limit than the mean speed in the rural areas. Further-more, the speeds at the top end of the speed distribution (above the 85th percentile) were very high, particularly in rural areas. This is a concern because, as discussed in the first section of this Part, the open road in New Zealand was designed for speeds of approximately 80 kph, with some sections of road upgraded to a 100-kph design speed. A large proportion of drivers are therefore travelling at speeds above the speed for which the road was designed to be safely travelled on. This means that drivers travelling above the design speed who encounter objects on the road in the dis-tance will have less chance of stopping under emergency braking and avoiding a collision with the object. Also, by travelling above the design speed, there is a high chance of losing control of the vehicle on curves. As seen above, the loss of control scenario represented a large proportion of the crashes in which excessive speed was a contributing factor.
The high mean speed in urban areas is also of concern because of the presence of vulnerable road users. For example, a pedestrian hit by a vehicle at the 1999 mean speed of 55.8 kph would have over an 80% chance of being killed (see Figure A15, in Part A). Furthermore, the chance of a pedestrian being killed if hit by the fastest 15% of urban traffic before their brakes are applied is close to 100%.
It is estimated that, if the rural mean speed could be reduced by 4 kph, from 102 to 98 kph, there would be fewer people killed and injured on New Zealand’s rural roads each year. Nilsson’s formulae from Section 1a of Part A can be used to calculate the size of the reduction in deaths and injuries from reducing the rural mean speed. Although the formulae apply to crash reductions, they can be generalised to injury reductions because the ratio of casualties to crashes remains approximately constant.
Table E6 displays the injury savings when the mean speed is reduced from 102 to 98 kph. For example, in 1998 350 people were killed on New Zealand’s rural roads. Apply-ing Nilsson’s formula, we can see that the number of people killed if the mean speed was reduced from 102 to 98 kph would be 298. Hence 52 people’s lives would have been saved if the mean speed was reduced by 4 kph. Similarly applying Nilsson’s formula, the 4-kph mean speed reduction would save 185 people from being fatally or seriously injured, and would save 442 people from being injured in a crash.
Table E6 – Injury savings on rural roads in 1998 given a reduction in the mean speed from 102 to 98 kph
Source: LTSA Crash Analysis System.
Attitude Data
The New Zealand Public Attitudes Survey has been undertaken periodically since 1974, and annually since 1994, to evaluate attitudes to road safety issues, primarily alcohol-impaired driving and speed. Face-to-face interviews about these issues are conducted in May and June of each year with respondents aged 15 and over, in towns, cities, and rural areas throughout New Zealand. In 1999, 1,645 people were interviewed, including 1,417 who held drivers’
licences (LTSA, 1999a).
New Zealanders’ awareness of speed as a road safety issue in 1999 has dropped slightly since 1998, returning to 1997 levels. When asked what factors make travelling on New Zealand roads unsafe, just over half spontaneously mentioned speeding (see Figure E9). One fifth (21%) identified speed as the main factor that made New Zealand roads unsafe.
Figure E9 – Things that make travelling on NZ roads unsafe: speed
Source: LTSA (1999a).
Injury Type Number of Nilsson’s Formulae: Number of Injuries Number of Injuries if Injuries
in 1998 Mean Speed Reduced Saved (rural roads) from 102 to 98 kph
Fatal 350 (98/102)
4
x 350 = 298 52
Fatal and Serious 1,634 (98/102)
3
77 Despite this recognition of speed as a major road safety
issue, the speeding culture is still strong. For example, 44%
of male drivers and 32% of female drivers say that they enjoy driving fast on the open road. This attitude is particularly strong among drivers under 35 years (see Figure E10). For example, 56% of 25- to 29-year-olds say that they enjoy driving fast on the open road.
Figure E10 – Percentage of drivers in each age group that said they enjoy driving fast on the open road.
Source: LTSA (1999a).
The perceived risk of a crash when speeding is not understood as well as the perceived risk of a crash when drink-driving (see Figure E11). For example, 22% of male drivers and 14% of female drivers agree that “there isn’t much chance of an accident when speeding if you are careful”. In comparison, 10% of male drivers and six percent of female drivers agree that “there isn’t much chance of an accident when driving after drinking if you are careful”. Drivers in the 50-plus age group are more likely to agree with the statement
“there isn’t much chance of an accident when speeding if you are careful” than younger drivers. For example, 26% of drivers in the 60-plus age group agreed with the statement, compared to 13% of 20- to 24-year-old drivers.
Figure E11 – Percentage of New Zealanders who agreed or strongly agreed with the statements “There is not much chance of an accident if you’re careful when speeding” or
“when driving after drinking”
Source: LTSA (1999a).
The findings relating to speed enforcement were generally positive. They were:
• Three-quarters of New Zealand adults agree that enforcing the speed limit helps to reduce the road toll. However, 41% think that the risk of being caught speeding is small.
• Fewer New Zealanders now believe that penalties for speeding are not very severe. In 1997, 38% of people agreed with this statement, but by 1999 this had reduced to 32%.
• Sixteen percent of drivers (18% of males and 13% of females) reported receiving a speeding ticket in the previous year. Drivers under the age of 35 years were most likely to report receiving a speeding ticket (see Figure E12). For example, 23% of 15- to 19-year-old drivers reported receiving a speeding ticket in the previous year.
20 40 60
Percentage of Drivers
Age Group
15-19
20-24
25-29
30-34
35-49
50-59
60+
0
% Agree/Strongly Agree
30
25
20
15
10
5
1998 1997
1996
1995 1999
speeding
driving after drinking Not much chance of an accident if careful when…
Year of Survey
63The question about receiving a ticket if passing a speed camera implied that the speed camera was operational at the time.
Figure E12 – Percentage of drivers in each age group that reported receiving a speeding ticket in the previous year
Source: LTSA (1999a).
• Most people find extremely high speeds unacceptable.
Eighty-five percent supported automatic loss of licence for drivers caught speeding at 150 kph on the open road and 88% supported this for drivers caught at 90 kph in a 50-kph zone.
• Support for retaining speed limits at current levels was high (71% for open roads and 77% for 50-kph zones).
There was less support than in previous years for intro-ducing additional 60-kph and 80-kph speed limits for some roads (52% support in 1999, compared to 58%
in 1998 and 64% in 1995). These speed limits have been introduced in some areas over the last four years.
• Support for speed cameras has reduced slightly since 1998, back to 1997 levels. Sixty percent of New Zealanders agree that the use of speed cameras helps lower the road toll and 63% think that they are operated fairly (compared to 68% and 70% respectively in 1998).
Opinion is fairly evenly divided over whether speed cameras should be hidden or in full view, with many people supporting a mixture of the two modes.
• More people think that they would be likely to receive a ticket from a speed camera than from a police officer (see Figure E13). For instance, when driving at 120 kph
in a 100-kph zone, 83% would expect to receive a ticket from a speed camera63, but only 59% (an increase from 50% last year) would expect a ticket from a police officer who was present. The higher perceived risk of detection for speed cameras over police officers was discussed in Part C.
in a 100-kph zone, 83% would expect to receive a ticket from a speed camera63, but only 59% (an increase from 50% last year) would expect a ticket from a police officer who was present. The higher perceived risk of detection for speed cameras over police officers was discussed in Part C.